Lenovo YOGA Tablet 2-851F Owner's manual

YOGA TABLET 2
Hardware Maintenance Manual
YOGA Tablet 2-851F

Note:
Before using this information and the product it supports, be sure to read the general information
under “Notices” on page 83.
First Edition (Sep 2014)
© Copyright Lenovo 2014. All rights reserved.
LENOVO products, data, computer software, and services have been developed exclusively at private
expense and are sold to governmental entities as commercial items as defined by 48 C.F.R. 2.101 with
limited and restricted rights to use, reproduction and disclosure.
LIMITED AND RESTRICTED RIGHTS NOTICE: If products, data, computer software, or services are
delivered pursuant to a General Services Administration “GSA” contract, use, reproduction, or disclo-
sure is subject to restrictions set forth in Contract No. GS-35F-05925.
© 2014 Lenovo

iii
About this manual........................................iv
Safety information.........................................1
General safety ...................................................... 2
Electrical safety .................................................... 3
Safety inspection guide ...................................... 5
Handling devices that are sensitive to electro-
static discharge .................................................... 6
Grounding requirements ................................... 6
Safety notices: multilingual translations.......... 7
Laser compliance statement............................. 14
Important service information ...................16
Strategy for replacing FRUs............................. 16
Important notice for replacing a system
board ............................................................. 17
Important information about replacing RoHS
compliant FRUs ................................................. 18
General checkout........................................19
What to do first.................................................. 20
Power system checkout .................................... 21
Checking the Computer AC Charger....... 21
Checking the internal battery status......... 22
Related service information.......................23
Security ............................................................... 23
Power management .......................................... 23
Activating/Deactivating the Display........ 23
Lenovo 851 ..................................................24
Specifications ..................................................... 24
FRU replacement notices.................................. 26
Screw notices................................................ 26
Removing and replacing an FRU.................... 27
1010 Rear cover............................................ 28
1020 Right speaker ...................................... 31
1030 Sub board............................................. 34
1040 LCD FPC.............................................. 38
1050 Main FPC............................................. 41
1060 Hall sensor FPC .................................. 44
1070 Main board.......................................... 47
1080 Left speaker......................................... 55
1090 Rear camera......................................... 59
1100 USB and volume key FPC................. 61
1110 Volume key ......................................... 63
1120 WIFI2 antenna..................................... 64
1130 GPS/WIFI1 antenna............................ 66
1140 Windows key ...................................... 68
1150 Battery pack......................................... 69
1160 Power key............................................ 74
Locations ............................................................. 76
Front view.....................................................76
Rear view ...................................................... 77
Parts list...............................................................78
Overall...........................................................78
Screws............................................................82
Notices .........................................................83
Trademarks......................................................... 84
Contents

iv
This manual contains service and reference information for the following
Lenovo product of the specified versions:
•Lenovo 851 (WiFi version)
Use this manual to troubleshoot problems.
The manual is divided into the following sections:
• The common sections provide general information, guidelines, and safety
information required for servicing computers.
• The product-specific section includes service, reference, and product-specific
parts information.
About this manual
Note:
The information provided in this manual is applicable to both product
versions mentioned above, unless otherwise specified.
Important:
This manual is intended only for trained servicers who are familiar with
Lenovo products. Use this manual to troubleshoot problems effectively.
Before servicing a Lenovo product, make sure to read all the information
under “Safety information” on page 1 and “Important service information”
on page 16.

Safety information
1
This chapter presents the following safety information that you need to get
familiar with before you service a Lenovo computer:
•“Generalsafety”onpage2
• “Electrical safety” on page 3
• “Safety inspection guide” on page 5
• “Handling devices that are sensitive to electrostatic discharge” on page 6
• “Grounding requirements” on page 6
• “Safety notices: multilingual translations” on page 7
• “Laser compliance statement” on page 14
Safety information

Lenovo 851 Hardware Maintenance Manual
2
Follow these rules below to ensure general safety:
• Observe a good housekeeping in the area where the machines are put during
and after the maintenance.
• When lifting any heavy object:
1. Make sure that you can stand safely without slipping.
2. Distribute the weight of the object equally between your feet.
3. Use a slow lifting force. Never move suddenly or twist when you attempt
to lift it.
4. Lift it by standing or pushing up with your leg muscles; this action could
avoid the strain from the muscles in your back. Do not attempt to lift any
object that weighs more than 16 kg (35 lb) or that you think is too heavy for
you.
• Do not perform any action that causes hazards to the customer, or that makes
the machine unsafe.
• Before you start the machine, make sure that other service representatives
and the customer are not in a hazardous position.
• Place removed covers and other parts in a safe place, keeping them away
from all personnel, while you are servicing the machine.
• Keep your toolcase away from walk areas so that other people will not trip it
over.
• Do not wear loose clothing that can be trapped in the moving parts of the
machine. Make sure that your sleeves are fastened or rolled up above your
elbows. If your hair is long, fasten it.
• Insert the ends of your necktie or scarf inside clothing or fasten it with the
nonconductive clip, about 8 centimeters (3 inches) from the end.
• Do not wear jewelry, chains, metal-frame eyeglasses, or metal fasteners for
your clothing.
Attention: Metal objects are good electrical conductors.
• Wear safety glasses when you are hammering, drilling, soldering, cutting
wire, attaching springs, using solvents, or working in any other conditions
that may be hazardous to your eyes.
• After service, reinstall all safety shields, guards, labels, and ground wires.
Replace any safety device that is worn or defective.
• Reinstall all covers correctly before returning the machine to the customer.
• Fan louvers on the machine help to prevent the overheating of internal
components. Do not obstruct fan louvers or cover them with labels or
stickers.
General safety

Safety information
3
Observe the following rules when working on electrical equipments.
• Find the room emergency power-off (EPO) switch for disconnecting the
switch or electrical outlet. If an electrical accident occurs, you can then
operate the switch or unplug the power cord quickly.
• Do not work alone under hazardous conditions or near the equipment that
has hazardous voltages.
• Disconnect all power before:
—Performing a mechanical inspection
—Working near power supplies
—Removing or installing main units
• Before you start to work on the machine, unplug the power cord. If you
cannot unplug it, ask the customer to power-off the wall box that supplies
power to the machine, and to lock the wall box in the off position.
• If you need to work on a machine that has exposed electrical circuits, observe
the following precautions:
—Ensure that another person, familiar with the power-off controls, is near
you.
Attention: Another person must be there to switch off the power, if
necessary.
—Use only one hand when working with powered-on electrical equipment;
keep the other hand in your pocket or behind your back.
Attention: An electrical shock can occur only when there is a complete
circuit. By observing the above rule, you may prevent a current from
passing through your body.
—When using testers, set the controls correctly and use the approved probe
leads and accessories for that tester.
—Stand on suitable rubber mats (obtained locally, if necessary) to insulate
you from grounds such as metal floor strips and machine frames.
Observe the special safety precautions when you work with very high voltages;
instructions for these precautions are in the safety sections of maintenance
information. Be extremely careful when you measure the high voltages.
• Regularly inspect and maintain your electrical hand tools for safe operational
condition.
• Do not use worn or broken tools and testers.
• Never assume that power has been disconnected from a circuit. First, check it
to make sure that it has been powered off.
Electrical safety
Important:
Use only approved tools and test equipments. Some hand tools have
handles covered with a soft material that does not insulate you when
working with live electrical currents.
Many customers have rubber floor mats near their machines that contain
small conductive fibers to decrease electrostatic discharges. Do not use such
kind of mat to protect yourself from electrical shock.

Lenovo 851 Hardware Maintenance Manual
4
• Always look carefully for possible hazards in your work area. Examples of
these hazards are moist floors, nongrounded power extension cables, power
surges, and missing safety grounds.
• Do not touch live electrical circuits with the reflective surface of a plastic
dental mirror. The surface is conductive; such touching can cause personal
injury and machine damage.
• Do not service the following parts with the power on when they are removed
from their normal operating places in a machine:
—Power supply units
—Pumps
—Blowers and fans
—Motor generators
and similar units. (This practice ensures correct grounding of the units.)
• If an electrical accident occurs:
—Caution: do not become a victim yourself.
—Switch off the power.
—Send the victim to get medical aid.

Safety information
5
The purpose of this inspection guide is to assist you in identifying potential
unsafe conditions. As each machine was designed and built, required safety
items were installed to protect users and service personnel from injury. This
guide addresses only those items. You should use good judgment to identify
potential safety hazards according to the attachment of non-Lenovo features or
options not covered by this inspection guide.
If any unsafe conditions are present, you must determine how serious the
apparent hazard could be and whether you can continue without first correcting
the problem.
Consider these conditions and the safety hazards they present:
• Electrical hazards, especially primary power (primary voltage on the frame
can cause serious or fatal electrical shock)
• Explosive hazards, such as a damaged CRT face or a bulging capacitor
• Mechanical hazards, such as loose or missing hardware
To determine whether there are any potential unsafe conditions, use the
following checklist at the beginning of every service task. Begin the checks with
the power off, and the power cord disconnected.
Checklist:
1. Check exterior covers for damage (loose, broken, or sharp edges).
2. Turn off the computer. Disconnect the power cord.
3. Check the power cord for:
a. A third-wire ground connector in good condition. Use a meter to measure
third-wire ground continuity for 0.1 ohm or less between the external
ground pin and the frame ground.
b. The power cord should be the type specified in the parts list.
c. Insulation must not be frayed or worn.
4. Check for cracked or bulging batteries.
5. Remove the cover.
6. Check for any obvious non-Lenovo alterations. Use good judgment as to the
safety of any non-Lenovo alterations.
7. Check inside the unit for any obvious unsafe conditions, such as metal filings,
contamination, water or other liquids, or signs of fire or smoke damage.
8. Check for worn, frayed, or pinched cables.
9. Check that the power-supply cover fasteners (screws or rivets) have not been
removed or tampered with.
Safety inspection guide

Lenovo 851 Hardware Maintenance Manual
6
Any computer part containing transistors or integrated circuits (ICs) should be
considered sensitive to electrostatic discharge (ESD). ESD damage can occur
when there is a difference in chargebetween objects. Protect against ESD damage
by equalizing the charge so that the machine, the part, the work mat, and the
person handling the part are all at the same charge.
When handling ESD-sensitive parts:
• Keep the parts in protective packages until they are inserted into the product.
• Avoid contact with other people.
• Wear a grounded wrist strap against your skin to eliminate static on your
body.
• Prevent the part from touching your clothing. Most clothing is insulative and
retains a charge even when you are wearing a wrist strap.
• Use the black side of a grounded work mat to provide a static-free work
surface. The mat is especially useful when handling ESD-sensitive devices.
• Select a grounding system, such as those listed below, to provide protection
that meets the specific service requirement.
—Attach the ESD ground clip to any frame ground, ground braid, or green-
wire ground.
—When working on a double-insulated or battery-operated system, use an
ESD common ground or reference point. You can use coax or connector-
outside shells on these systems.
—Use the round ground prong of the ac plug on ac-operated computers.
Electrical grounding of the computer is required for operator safety and correct
system function. Proper grounding of the electrical outlet can be verified by a
certified electrician.
Handling devices that are sensitive to electrostatic discharge
Notes:
1. Use product-specific ESD procedures when they exceed the
requirements noted here.
2. Make sure that the ESD protective devices you use have been certified
(ISO 9000) as fully effective.
Notes:
The use of a grounding system to guard against ESD damage is desirable but
not necessary.
Grounding requirements

Safety information
7
The safety notices in this section are provided in English, French, German,
Hebrew, Italian, Japanese, and Spanish.
Safety notices: multilingual translations
Safety notice 1
Before the computer is powered on after FRU replacement, make sure all
screws, springs, and other small parts are in place and are not left loose
inside the computer. Verify this by shaking the computer and listening for
rattling sounds. Metallic parts or metal flakes can cause electrical shorts.
Avant de remettre l’ordinateur sous tension après remplacement d’une unité
en clientèle, vérifiez que tous les ressorts, vis et autres pièces sont bien en
place et bien fixées. Pour ce faire, secouez l’unité et assurez-vous qu’aucun
bruit suspect ne se produit. Des pièces métalliques ou des copeaux de métal
pourraient causer un court-circuit.
Bevor nach einem FRU-Austausch der Computer wieder angeschlossen
wird, muß sichergestellt werden, daß keine Schrauben, Federn oder andere
Kleinteile fehlen oder im Gehäuse vergessen wurden. Der Computer muß
geschüttelt und auf Klappergeräusche geprüft werden. Metallteile oder-
splitter können Kurzschlüsse erzeugen.
Prima di accendere l’elaboratore dopo che é stata effettuata la sostituzione di
una FRU, accertarsi che tutte le viti, le molle e tutte le altri parti di piccole
dimensioni siano nella corretta posizione e non siano sparse all’interno
dell’elaboratore. Verificare ciò scuotendo l’elaboratore e prestando
attenzione ad eventuali rumori; eventuali parti o pezzetti metallici possono
provocare cortocircuiti pericolosi.
Antes de encender el sistema despues de sustituir una FRU, compruebe que
todos los tornillos, muelles y demás piezas pequeñas se encuentran en su
sitio y no se encuentran sueltas dentro del sistema. Compruébelo agitando el
sistema y escuchando los posibles ruidos que provocarían. Las piezas
metálicas pueden causar cortocircuitos eléctricos.

Lenovo 851 Hardware Maintenance Manual
8
Safety notice 2
DANGER
Some standby batteries contain a small amount of nickel and cadmium. Do
not disassemble a standby battery, recharge it, throw it into fire or water, or
short-circuit it. Dispose of the battery as required by local ordinances or
regulations. Use only the battery in the appropriate parts listing. Use of an
incorrect battery can result in ignition or explosion of the battery.
Certaines batteries de secours contiennent du nickel et du cadmium. Ne les
démontez pas, ne les rechargez pas, ne les exposez ni au feu ni à l’eau. Ne
les mettez pas en court-circuit. Pour les mettre au rebut, conformez-vous à
la réglementation en vigueur. Lorsque vous remplacez la pile de sauvegarde
ou celle de l’horloge temps réel, veillez à n’utiliser que les modèles cités dans
la liste de pièces détachées adéquate. Une batterie ou une pile inappropriée
risque de prendre feu ou d’exploser.
Die Bereitschaftsbatterie, die sich unter dem Diskettenlaufwerk befindet,
kann geringe Mengen Nickel und Cadmium enthalten. Sie darf nicht
zerlegt, wiederaufgeladen, kurzgeschlossen, oder Feuer oder Wasser
ausgesetzt werden. Bei der Entsorgung die örtlichen Bestimmungen für
Sondermüll beachten. Beim Ersetzen der Bereitschafts-oder Systembatterie
nur Batterien des Typs verwenden, der in der Ersatzteilliste aufgeführt ist.
Der Einsatz falscher Batterien kann zu Entzündung oder Explosion führen.
Alcune batterie di riserva contengono una piccola quantità di nichel e
cadmio. Non smontarle, ricaricarle, gettarle nel fuoco o nell’acqua né
cortocircuitarle. Smaltirle secondo la normativa in vigore (DPR 915/82,
successive disposizioni e disposizioni locali). Quando si sostituisce la
batteria dell’RTC (real time clock) o la batteria di supporto, utilizzare
soltanto i tipi inseriti nell’appropriato Catalogo parti. L’impiego di una
batteria non adatta potrebbe determinare l’incendio o l’esplosione della
batteria stessa.
Algunas baterías de reserva contienen una pequeña cantidad de níquel y
cadmio. No las desmonte, ni recargue, ni las eche al fuego o al agua ni las
cortocircuite. Deséchelas tal como dispone la normativa local. Utilice sólo
baterías que se encuentren en la lista de piezas. La utilización de una batería
no apropiada puede provocar la ignición o explosión de la misma.

Safety information
9
Safety notice 3
DANGER
The battery pack contains small amounts of nickel. Do not disassemble it,
throw it into fire or water, or short-circuit it. Dispose of the battery pack as
required by local ordinances or regulations. Use only the battery in the
appropriate parts listing when replacing the battery pack. Use of an
incorrect battery can result in ignition or explosion of the battery.
La batterie contient du nickel. Ne la démontez pas, ne l’exposez ni au feu ni
à l’eau. Ne la mettez pas en court-circuit. Pour la mettre au rebut,
conformez-vous à la réglementation en vigueur. Lorsque vous remplacez la
batterie, veillez à n’utiliser que les modèles cités dans la liste de pièces
détachées adéquate. En effet, une batterie inappropriée risque de prendre
feu ou d’exploser.
Akkus enthalten geringe Mengen von Nickel. Sie dürfen nicht zerlegt,
wiederaufgeladen, kurzgeschlossen, oder Feuer oder Wasser ausgesetzt
werden. Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll
beachten. Beim Ersetzen der Batterie nur Batterien des Typs verwenden, der
in der Ersatzteilliste aufgeführt ist. Der Einsatz falscher Batterien kann zu
Entzündung oder Explosion führen.
La batteria contiene piccole quantità di nichel. Non smontarla, gettarla nel
fuoco o nell’acqua né cortocircuitarla. Smaltirla secondo la normativa in
vigore (DPR 915/82, successive disposizioni e disposizioni locali). Quando si
sostituisce la batteria, utilizzare soltanto i tipi inseriti nell’appropriato
Catalogo parti. L’impiego di una batteria non adatta potrebbe determinare
l’incendio o l’esplosione della batteria stessa.
Las baterías contienen pequeñas cantidades de níquel. No las desmonte, ni
recargue, ni las eche al fuego o al agua ni las cortocircuite. Deséchelas tal
como dispone la normativa local. Utilice sólo baterías que se encuentren en
la lista de piezas al sustituir la batería. La utilización de una batería no
apropiada puede provocar la ignición o explosión de la misma.

Lenovo 851 Hardware Maintenance Manual
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Safety notice 4
DANGER
The lithium battery can cause a fire, an explosion, or a severe burn. Do not
recharge it, remove its polarized connector, disassemble it, heat it above
100°C (212°F), incinerate it, or expose its cell contents to water. Dispose of
the battery as required by local ordinances or regulations. Use only the
battery in the appropriate parts listing. Use of an incorrect battery can result
in ignition or explosion of the battery.
La pile de sauvegarde contient du lithium. Elle présente des risques
d’incendie, d’explosion ou de brûlures graves. Ne la rechargez pas, ne
retirez pas son connecteur polarisé et ne la démontez pas. Ne l’exposez pas
à une temperature supérieure à 100°C, ne la faites pas brûler et n’en exposez
pas le contenu à l’eau. Mettez la pile au rebut conformément à la
réglementation en vigueur. Une pile inappropriée risque de prendre feu ou
d’exploser.
Die Systembatterie ist eine Lithiumbatterie. Sie kann sich entzünden,
explodieren oder schwere Verbrennungen hervorrufen. Batterien dieses
Typs dürfen nicht aufgeladen, zerlegt, über 100 C erhitzt oder verbrannt
werden. Auch darf ihr Inhalt nicht mit Wasser in Verbindung gebracht oder
der zur richtigen Polung angebrachte Verbindungsstecker entfernt werden.
Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll beachten.
Beim Ersetzen der Batterie nur Batterien des Typs verwenden, der in der
Ersatzteilliste aufgeführt ist. Der Einsatz falscher Batterien kann zu
Entzündung oder Explosion führen.
La batteria di supporto e una batteria al litio e puo incendiarsi, esplodere o
procurare gravi ustioni. Evitare di ricaricarla, smontarne il connettore
polarizzato, smontarla, riscaldarla ad una temperatura superiore ai 100
gradi centigradi, incendiarla o gettarla in acqua. Smaltirla secondo la
normativa in vigore (DPR 915/82, successive disposizioni e disposizioni
locali). L’impiego di una batteria non adatta potrebbe determinare
l’incendio o l’esplosione della batteria stessa.
La batería de repuesto es una batería de litio y puede provocar incendios,
explosiones o quemaduras graves. No la recargue, ni quite el conector
polarizado, ni la desmonte, ni caliente por encima de los 100°C (212°F), ni la
incinere ni exponga el contenido de sus celdas al agua. Deséchela tal como
dispone la normativa local.

Safety information
11
Safety notice 5
If the LCD breaks and the fluid from inside the LCD gets into your eyes or
on your hands, immediately wash the affected areas with water at least for
15 minutes. Seek medical care if any symptoms caused by the fluid are
present after washing.
Si le panneau d’affichage à cristaux liquides se brise et que vous recevez dans
les yeux ou sur les mains une partie du fluide, rincez-les abondamment
pendant au moins quinze minutes. Consultez un médecin si des symptômes
persistent après le lavage.
Die Leuchtstoffröhre im LCD-Bildschirm enthält Quecksilber. Bei der
Entsorgung die örtlichen Bestimmungen für Sondermüll beachten. Der
LCD-Bildschirm besteht aus Glas und kann zerbrechen, wenn er
unsachgemäß behandelt wird oder der Computer auf den Boden fällt. Wenn
der Bildschirm beschädigt ist und die darin befindliche Flüssigkeit in
Kontakt mit Haut und Augen gerät, sollten die betroffenen Stellen
mindestens 15 Minuten mit Wasser abgespült und bei Beschwerden
anschließend ein Arzt aufgesucht werden.
Nel caso che caso l’LCD si dovesse rompere ed il liquido in esso contenuto
entrasse in contatto con gli occhi o le mani, lavare immediatamente le parti
interessate con acqua corrente per almeno 15 minuti; poi consultare un
medico se i sintomi dovessero permanere.
Si la LCD se rompe y el fluido de su interior entra en contacto con sus ojos o
sus manos, lave inmediatamente las áreas afectadas con agua durante
15 minutos como mínimo. Obtenga atención medica si se presenta algún

Lenovo 851 Hardware Maintenance Manual
12
Safety notice 6
DANGER
To avoid shock, do not remove the plastic cover that protects the lower part
of the inverter card.
Afin d’éviter tout risque de choc électrique, ne retirez pas le cache en
plastique protégeant la partie inférieure de la carte d’alimentation.
Aus Sicherheitsgründen die Kunststoffabdeckung, die den unteren Teil der
Spannungswandlerplatine umgibt, nicht entfernen.
Per evitare scosse elettriche, non rimuovere la copertura in plastica che
avvolge la parte inferiore della scheda invertitore.
Para evitar descargas, no quite la cubierta de plástico que rodea la parte baja
de la tarjeta invertida.
Safety notice 7
DANGER
Though the main batteries have low voltage, a shorted or grounded battery
can produce enough current to burn personnel or combustible materials.
Bien que le voltage des batteries principales soit peu élevé, le court-circuit ou
la mise à la masse d’une batterie peut produire suffisamment de courant
pour brûler des matériaux combustibles ou causer des brûlures corporelles
graves.
Obwohl Hauptbatterien eine niedrige Spannung haben, können sie doch bei
Kurzschluß oder Erdung genug Strom abgeben, um brennbare Materialien
zu entzünden oder Verletzungen bei Personen hervorzurufen.
Sebbene le batterie di alimentazione siano a basso voltaggio, una batteria in
corto circuito o a massa può fornire corrente sufficiente da bruciare materiali
combustibili o provocare ustioni ai tecnici di manutenzione.
Aunque las baterías principales tienen un voltaje bajo, una batería
cortocircuitada o con contacto a tierra puede producir la corriente suficiente
como para quemar material combustible o provocar quemaduras en el
personal.

Safety information
13
Safety notice 8
DANGER
Before removing any FRU, turn off the computer, unplug all power cords
from electrical outlets, remove the battery pack, and then disconnect any
interconnecting cables.
Avant de retirer une unité remplaçable en clientèle, mettez le système hors
tension, débranchez tous les cordons d’alimentation des socles de prise de
courant, retirez la batterie et déconnectez tous les cordons d’interface.
Die Stromzufuhr muß abgeschaltet, alle Stromkabel aus der Steckdose
gezogen, der Akku entfernt und alle Verbindungskabel abgenommen sein,
bevor eine FRU entfernt wird.
Prima di rimuovere qualsiasi FRU, spegnere il sistema, scollegare dalle prese
elettriche tutti i cavi di alimentazione, rimuovere la batteria e poi scollegare
i cavi di interconnessione.
Antes de quitar una FRU, apague el sistema, desenchufe todos los cables de
las tomas de corriente eléctrica, quite la batería y, a continuación, desconecte
cualquier cable de conexión entre dispositivos.

Lenovo 851 Hardware Maintenance Manual
14
Some models of Lenovo computer are equipped from the factory with an optical
storage device such as a CD-ROM drive or a DVD-ROM drive. Such devices are
also sold separately as options. If one of these drives is installed, it is certified in
the U.S. to conform to the requirements of the Department of Health and Human
Services 21 Code of Federal Regulations (DHHS 21 CFR) Subchapter J for Class
1 laser products. Elsewhere, the drive is certified to conform to the requirements
of the International Electrotechnical Commission (IEC) 825 and CENELEC EN 60
825 for Class 1 laser products.
If a CD-ROM drive, a DVD-ROM drive, or another laser device is installed, note
the following:
Opening the CD-ROM drive, the DVD-ROM drive, or any other optical storage
device could result in exposure to hazardous laser radiation. There are no
serviceable parts inside those drives. Do not open.
Laser compliance statement
CAUTION
Use of controls or adjustments or performance of procedures other than
those specified herein might result in hazardous radiation exposure.
O uso de controles, ajustes ou desempenho de procedimentos diferentes
daqueles aqui especificados pode resultar em perigosa exposição à radiação.
Pour éviter tout risque d’exposition au rayon laser, respectez les consignes
de réglage et d’utilisation des commandes, ainsi que les procédures décrites.
Werden Steuer- und Einstellelemente anders als hier festgesetzt verwendet,
kann gefährliche Laserstrahlung auftreten.
L’utilizzo di controlli, regolazioni o l’esecuzione di procedure diverse da
quelle specificate possono provocare l’esposizione a.
El uso de controles o ajustes o la ejecución de procedimientos distintos de los
aquí especificados puede provocar la exposición a radiaciones peligrosas.

Safety information
15
A CD-ROM drive, a DVD-ROM drive, or any other storage device installed may
contain an embedded Class 3A or Class 3B laser diode. Note the following:
DANGER
Emits visible and invisible laser radiation when open. Do not stare into the
beam, do not view directly with optical instruments, and avoid direct
exposure to the beam.
Radiação por raio laser ao abrir. Não olhe fixo no feixe de luz, não olhe
diretamente por meio de instrumentos óticos e evite exposição direta com o
feixe de luz.
Rayonnement laser si carter ouvert. Évitez de fixer le faisceau, de le regarder
directement avec des instruments optiques, ou de vous exposer au rayon.
Laserstrahlung bei geöffnetem Gerät. Nicht direkt oder über optische
Instrumente in den Laserstrahl sehen und den Strahlungsbereich meiden.
Kinyitáskor lézersugár ! Ne nézzen bele se szabad szemmel, se optikai
eszközökkel. Kerülje a sugárnyalábbal való érintkezést!
Aprendo l’unità vengono emesse radiazioni laser. Non fissare il fascio, non
guardarlo direttamente con strumenti ottici e evitare l’esposizione diretta al
fascio.
Radiación láser al abrir. No mire fijamente ni examine con instrumental
óptico el haz de luz. Evite la exposición directa al haz.

Lenovo 851 Hardware Maintenance Manual
16
This chapter presents the following important service information:
• “Strategy for replacing FRUs” on page 16
—“Important notice for replacing a system board” on page 17
• “Important information about replacing RoHS compliant FRUs” on page 18
Before replacing parts:
Make sure that all software fixes, drivers, and BIOS downloads are installed
before replacing any FRUs listed in this manual.
After a system board is replaced, ensure that the latest BIOS is loaded to the
system board before completing the service action.
To download software fixes, drivers, and BIOS, follow the steps below:
1. Go to http://consumersupport.lenovo.com/.
2. Enter a serial number or select a product or use Lenovo smart downloading.
3. Select the BIOS/Driver/Applications and download.
4. Follow the directions on the screen and install the necessary software.
Use the following strategy to prevent unnecessary expense for replacing and
servicing FRUs:
• If you are instructed to replace an FRU, but the replacement does not solve
the problem, reinstall the original FRU before you continue.
• Some computers have both a processor board and a system board. If you are
instructed to replace either of them, and replacing one of them does not solve
the problem, reinstall that board, and then replace the other one.
• If an adapter or a device consists of more than one FRU, any of the FRUs may
be the cause of the error. Before replacing the adapter or device, remove the
FRUs one by one to see if the symptoms change. Replace only the FRU that
changed the symptoms.
Attention: The setup configuration on the computer you are servicing may have
been customized. Running Automatic Configuration may alter the settings. Note
the current configuration settings (using the View Configuration option); then,
when service has been completed, verify that those settings remain in effect.
Important service information
Important:
BIOS and device driver fixes are customer-installable. The BIOS and device
drivers are posted on the customer support site:
http://consumersupport.lenovo.com/.
Strategy for replacing FRUs